UK Prime Minister Boris Johnson, under fire for holding lockdown parties in Downing Street, is facing a no-confidence vote on Monday that could result in his removal as both the country’s leader, as well as the leader of the Conservative Party.

While rumours about an impending no-confidence vote had been doing rounds over the weekend, Conservative official Graham Brady on Monday confirmed that he had received enough letters from Members of Parliament to initiate the proceedings against Johnson.

A minimum of 54 Conservative MPs – or 15% of the party’s strength in the House of Commons – are required to call for a no-confidence vote for the motion to pass. While the exact number of letters demanding the vote is not known, it is understood that the minimum threshold has been crossed.

Also read | United Kingdom PM Boris Johnson jeered at Queen Elizabeth’s Platinum Jubilee service

As it stands, the no-confidence vote is set to take place on Monday as an in-person event in the House of Commons, between 5pm and 7pm local time.

If 180 Conservative Party members, more than 50% of the party’s 359 members in the House of Commons, vote against Johnson on Monday, the embattled 57-year-old will be replaced as the country’s Prime Minister, as well as the party’s leader.

However, if Johnson wins the vote, no challenges to his leadership can be mounted for a year.

Also read | UK ‘partygate’ report blames culture of PM Boris Johnson’s office

Commenting on the decision to hold a no-confidence vote, a Downing Street spokesperson said it was the perfect opportunity “to draw a line and move on.”

“The PM welcomes the opportunity to make his case to MPs and will remind them that when they’re united and focused on the issues that matter to voters there is no more formidable political force,” the spokesperson added.

Political observers, however, think that it is unlikely that 50% of Conservative MPs will vote against Johnson.